High-utilization-rate water treatment device and method

Abstract

The invention discloses a high-utilization-rate water treatment device and method, and relates to the technical field of water treatment, and the high-utilization-rate water treatment device comprises a raw water pretreatment unit, a first-stage filtering unit, a second-stage filtering unit and a continuous electrodeionization unit which are connected in sequence; the primary filtering unit is connected with a pure water outlet module, the secondary filtering unit is connected with a pure water outlet module, the continuous electrodeionization unit is connected with an ultrapure water outlet module, wastewater outlets of the primary filtering unit and the secondary filtering unit are connected with a recycled wastewater pretreatment unit in parallel, and a pure water outlet of the recycled wastewater pretreatment unit is connected with an inlet of the primary filtering unit. The problems that a water treatment system in the traditional technology cannot meet the core requirements of low ions, low TOC and low particulate matter in the electroplating industry, the produced water quality fluctuation is large, a plating solution fails easily, and the defect rate of a plating layer is increased are solved; water resources are wasted, and the environmental protection pressure of high-salinity wastewater treatment is increased; and the problems that the dispersion capacity of a plating solution is reduced and a plating layer is not uniform due to impurity accumulation are solved.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and more specifically to a high-utilization-rate water treatment device and method. Background Technology

[0002] The core objective of electroplating production is to obtain a uniform, dense, corrosion-resistant, and strongly adhesive metal coating, and water quality directly determines the coating quality and production stability. Pure water / ultrapure water is indispensable in the entire electroplating process, and specific applications include: Pre-plating cleaning: It is necessary to remove oil, oxide scale and acid and alkali residues (such as chloride ions and sodium ions) from the surface of the workpiece to avoid impurities being introduced into the plating solution, which may cause pinholes, pits and spots in the plating layer. Plating solution preparation and replenishment: Used to dissolve electroplating chemicals such as nickel sulfate and stannous chloride. It is necessary to prevent impurities such as calcium and magnesium ions from reacting with the chemicals to form precipitates and to prevent the plating tank filter from clogging. Anode cleaning and activation: Clean the oxide film on the anode surface, maintain the stability of the pH value and impurity content of the plating solution, and ensure uniform conductivity of the anode; Post-processing: Rinse the product surface for residual plating solution, and prepare passivation solution and sealant to prevent impurities such as chloride ions from causing white frost or peeling of the passivation film; Environmental compliance: As rinsing water, it reduces the concentration of heavy metal ions and chloride ions in wastewater, lowers the difficulty of wastewater treatment, and meets the requirements of "water-saving electroplating".

[0003] A prior art patent with publication number CN104291492A discloses a solution comprising an electroplating wastewater storage tank, a cyanide breaking tank, a chromium removal tank, a flocculation tank, a sedimentation tank, a bottom sludge collection tank, a bottom sludge drying and pulverizing machine, an adsorption tank, and a reverse osmosis treatment device. The electroplating wastewater storage tank includes a first storage tank, a second storage tank, and a third storage tank. The first storage tank is connected to the cyanide breaking tank, the cyanide breaking tank is connected to the third storage tank, the second storage tank is connected to the chromium removal tank, the flocculation tank is connected to both the third storage tank and the chromium removal tank, the flocculation tank is connected to the sedimentation tank, the adsorption tank is connected to the sedimentation tank, and the reverse osmosis treatment device is connected to the adsorption tank.

[0004] As these existing devices, including those mentioned above, have been used, their shortcomings have gradually become apparent, mainly in the following aspects: First, existing water treatment systems have poor water quality adaptability. Traditional water treatment systems are mostly general-purpose and cannot meet the core requirements of low ion, low TOC, and low particulate matter in the electroplating industry. The output water quality fluctuates greatly, which can easily lead to plating solution failure and increased plating defect rate.

[0005] Secondly, conventional reverse osmosis systems have a water recovery rate of only 50%-75%, and a large amount of high-salt concentrated water is directly discharged, which not only wastes water resources but also increases the environmental pressure of high-salt wastewater treatment; the accumulation of impurities will lead to a decrease in the dispersion ability of the plating solution and uneven coating.

[0006] Third, the system requires frequent replacement of filter media and replenishment of fresh water, and the acid-base regeneration process generates secondary pollution, which does not conform to the green production trend of the electroplating industry. The existing system does not design a tiered water supply scheme that takes into account the differences in water usage at each stage of electroplating, and the mixing of ultrapure water and ordinary pure water results in wasted treatment costs.

[0007] In conclusion, the existing technology obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the Invention

[0008] In response to the shortcomings of existing technologies, this invention solves the problems of traditional water treatment systems failing to meet the core requirements of low ion, low TOC, and low particulate matter in the electroplating industry; large fluctuations in output water quality, which can easily lead to plating solution failure and increased plating defect rate; waste of water resources and increased environmental pressure on high-salt wastewater treatment; and the problem that impurity accumulation can lead to a decrease in the dispersion ability of the plating solution and uneven plating.

[0009] To address the above problems, the present invention provides the following technical solution: A high-efficiency water treatment device includes a raw water pretreatment unit, a primary filtration unit, a secondary filtration unit, and a continuous electro-desalination unit connected in sequence; the secondary filtration unit is connected to a pure water output module, and the continuous electro-desalination unit is connected to an ultrapure water output module. The primary filtration unit and the secondary filtration unit are connected in parallel to a wastewater pretreatment unit, and the purified water outlet of the wastewater pretreatment unit is connected to the inlet of the primary filtration unit.

[0010] As an optimized solution, the raw water pretreatment unit includes a raw water tank, a quartz sand filter, an activated carbon filter, a fine filter, and an intermediate water tank connected in sequence.

[0011] As an optimized solution, a raw water pump is connected between the raw water tank and the quartz sand filter, and a dosing tank is connected to the pipeline between the raw water pump and the quartz sand filter, as well as the pipeline between the activated carbon filter and the fine filter.

[0012] As an optimized solution, a heating unit is also connected to the raw water tank.

[0013] As an optimized solution, the primary filtration unit includes a primary high-pressure pump, a primary reverse osmosis module, and a primary water tank connected in sequence.

[0014] As an optimized solution, the secondary filtration unit includes a secondary high-pressure pump, a secondary reverse osmosis module, and a secondary water tank connected in sequence.

[0015] As an optimized solution, the continuous electro-desalination unit includes an electro-desalination high-pressure pump, a continuous electro-desalination module, and a pure water tank connected in sequence.

[0016] As an optimized solution, the wastewater pretreatment unit includes a recycling tank, a high-pressure pump, and a recycling reverse osmosis module connected in sequence.

[0017] As an optimized solution, the purified water outlet of the reverse osmosis recovery module is connected to the intermediate water tank.

[0018] As an optimized solution, the wastewater outlet of the primary reverse osmosis module is connected to the recovery water tank.

[0019] As an optimized solution, the wastewater outlet of the secondary reverse osmosis module is connected to the recovery water tank.

[0020] As an optimized solution, the pure water outlet module is connected to the secondary water tank.

[0021] As an optimized solution, the ultrapure water outlet module is connected to the pure water tank.

[0022] This invention also discloses a high-utilization-rate water treatment method, comprising the following steps: S1: Raw water pretreatment: Tap water undergoes three stages of filtration: a quartz sand filter, an activated carbon filter, and a fine filter, before entering an intermediate water tank for storage; water quality parameters are: turbidity ≤ 0.5 NTU, particulate matter content (≥ 1 μm) ≤ 20 particles / mL, suspended solids removal rate ≥ 90%; residual chlorine ≤ 0.05 mg / L, TOC ≤ 3 ppm, color ≤ 5 degrees, heavy metal ions ≤ 0.01 mg / L; S2: First-stage reverse osmosis purification: Water from the intermediate water tank is sent to the first-stage reverse osmosis unit via a first-stage high-pressure pump, and the initial purified water is stored in the first-stage water tank; the water quality parameters are conductivity ≤10μS / cm, desalination rate ≥99%, TOC ≤0.5ppm, microbial retention rate ≥99.9%, and total ionic impurity content ≤10ppm. S3: Two-stage reverse osmosis purification: Water from the first-stage water tank is sent to the second-stage reverse osmosis unit via a second-stage high-pressure pump, and the produced pure water is stored in the second-stage water tank; the water quality parameters are conductivity ≤1μS / cm, total desalination rate ≥99.5%, TOC ≤0.1ppm, silicon ions ≤0.05ppm, chloride ions ≤0.1ppm, suitable for pre-plating cleaning scenarios. S4: Continuous electro-desalination and purification: Water from the secondary water tank is sent to the continuous electro-desalination unit via an electro-desalination high-pressure pump, and ultrapure water is stored in the pure water tank; the water quality parameters are resistivity ≥18.2MΩ・cm (25℃), conductivity ≤0.055μS / cm, TOC ≤10ppb, ionic impurities ≤0.1ppb, and microorganisms ≤1CFU / mL, suitable for precision rinsing scenarios; S5: Concentrate recovery: Wastewater from the primary and secondary reverse osmosis units is stored in the recovery tank. After being treated by the recovery reverse osmosis module, the water in the recovery tank has a conductivity of ≤50μS / cm and a desalination rate of ≥98%, and is returned to the intermediate tank for recycling.

[0023] Compared with the prior art, the beneficial effects of the present invention are: The coating quality is improved, the output water quality is stable and meets the standards, and coating defects such as pinholes and pits are effectively avoided, reducing the product defect rate; Water resources are used efficiently, with a total water recovery rate of 85%-95%, which greatly reduces the consumption of fresh water and meets the requirements of water-saving electroplating. Operating costs are reduced, decreasing costs associated with plating solution waste, filter replacement, and wastewater treatment. Furthermore, continuous electro-desalination with online self-regeneration eliminates the need for acids and alkalis, thus reducing environmental protection costs. Environmental compliance is ensured, reducing the discharge of high-salt wastewater and lowering the concentration of heavy metal ions and chloride ions in the wastewater to meet the environmental standards of the electroplating industry. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0025] Figure 1 This is a schematic diagram of the structure of the present invention.

[0026] In the diagram: 1-Raw water pretreatment unit, 2-First-stage filtration unit, 3-Second-stage filtration unit, 4-Continuous electro-desalination unit, 5-Recycled wastewater pretreatment unit, 6-Pure water outlet module, 7-Ultrapure water outlet module, 8-Heating unit, 9-Raw water tank; 10-Quartz sand filter; 11-Activated carbon filter; 12-Intermediate water tank; 13-Raw water pump; 14-Fine filter; 15-First-stage high-pressure pump; 16-First-stage reverse osmosis module; 17-First-stage water tank; 18-Second-stage high-pressure pump; 19-Second-stage reverse osmosis module; 20-Second-stage water tank; 21-Electro-desalination high-pressure pump; 22-Dosing tank; 23-Continuous electro-desalination module; 24-Pure water tank; 25-Recycled water tank; 26-High-pressure pump; 27-Recycled reverse osmosis module. Detailed Implementation

[0027] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0028] like Figure 1As shown, the high-utilization-rate water treatment device includes a raw water pretreatment unit 1, a primary filtration unit 2, a secondary filtration unit 3, and a continuous electro-desalination unit 4 connected in sequence; the secondary filtration unit 3 is connected to a pure water outlet module 6, and the continuous electro-desalination unit 4 is connected to an ultrapure water outlet module 7. The wastewater outlets of the primary filtration unit 2 and the secondary filtration unit 3 are connected in parallel to a wastewater pretreatment unit 5, and the clean water outlet of the wastewater pretreatment unit 5 is connected to the inlet of the primary filtration unit 2.

[0029] The raw water pretreatment unit 1 includes a raw water tank 9, a quartz sand filter 10, an activated carbon filter 11, a fine filter 14, and an intermediate water tank 12 connected in sequence.

[0030] A raw water pump 13 is connected between the raw water tank 9 and the quartz sand filter 10. The pipeline between the raw water pump 13 and the quartz sand filter 10, as well as the pipeline between the activated carbon filter 11 and the fine filter 14, are respectively connected to a dosing tank 22.

[0031] A dosing tank is also provided between the primary water tank 17 and the secondary high-pressure pump 18.

[0032] Quartz sand filter 10 removes large particulate suspended solids, colloids, silt, rust and other physical impurities from raw water, reduces water turbidity, and protects subsequent precision filtration and membrane elements from being scratched or blocked by large particles.

[0033] The activated carbon filter 11 removes residual chlorine, organic matter, odor, and color from the raw water, while also adsorbing some heavy metal ions, thus preventing residual chlorine and organic matter from oxidizing and contaminating core components such as the subsequent reverse osmosis membrane.

[0034] The fine filter 14 serves as the final barrier in the pretreatment process, removing fine suspended solids and colloidal particles (typically retaining particle sizes ≥5μm or 1μm) remaining after the first two stages of filtration, thus thoroughly protecting subsequent precision components such as the reverse osmosis membrane from being scratched by particles.

[0035] The raw water tank 9 is also connected to a heating unit 8, which is turned on in winter to ensure that the water does not freeze.

[0036] The primary filtration unit 2 includes a primary high-pressure pump 15, a primary reverse osmosis module 16, and a primary water tank 17 connected in sequence.

[0037] The first-stage reverse osmosis module 16 is the core unit of the deep purification stage. Its processing precision is far higher than that of the pretreatment stage. It can significantly remove impurities such as ions and organic matter from the water, laying a key foundation for producing qualified pure water.

[0038] The secondary filtration unit 3 includes a secondary high-pressure pump 18, a secondary reverse osmosis module 19, and a secondary water tank 20 connected in sequence.

[0039] The secondary reverse osmosis module 19 is a deep desalination stage based on the filtration of the primary reverse osmosis module 16. It is mainly used to further purify the water quality to meet the demand for higher purity water.

[0040] The continuous electro-desalination unit 4 includes an electro-desalination high-pressure pump 21, a continuous electro-desalination module 23, and a pure water tank 24 connected in sequence.

[0041] The continuous electro-desalination module 23 combines ion exchange resin, ion exchange membrane and electric field for deep desalination technology, and is the core component of ultrapure water preparation.

[0042] The wastewater pretreatment unit 5 includes a recycling tank 25, a high-pressure pump 26, and a recycling reverse osmosis module 27 connected in sequence.

[0043] The process of adding a reverse osmosis module 27 to the wastewater recycling unit and returning its product water to the front end of the primary filtration unit 2 is the key to improving the overall water recovery rate of the pure water unit and reducing water waste.

[0044] The purified water outlet of the reverse osmosis module 27 is connected to the intermediate water tank 12, which improves the conversion rate of tap water and pure water, greatly reduces costs, and the water production rate of the entire water purification system is as high as 80% or more after recycling.

[0045] The wastewater outlet of the first-stage reverse osmosis module 16 is connected to the recovery water tank 25.

[0046] The wastewater outlet of the secondary reverse osmosis module 19 is connected to the recovery water tank 25.

[0047] The pure water output module 6 is connected to the secondary water tank 20.

[0048] The ultrapure water output module 7 is connected to the pure water tank 24.

[0049] The secondary reverse osmosis module 19 is like "double insurance". Even if the primary reverse osmosis module 16 is slightly contaminated or its performance deteriorates, the secondary reverse osmosis module 19 can make up for its insufficient treatment and prevent contaminants from entering the subsequent water use process. This invention also discloses a high-utilization-rate water treatment method, comprising the following steps: S1: Raw water pretreatment: Tap water is filtered through a three-stage process of quartz sand filter 10, activated carbon filter 11, and fine filter 14 before entering the intermediate water tank 12 for storage; the water quality parameters are: turbidity ≤0.5 NTU, particulate matter content (≥1 μm) ≤20 particles / mL, suspended solids removal rate ≥90%; residual chlorine ≤0.05 mg / L, TOC ≤3 ppm, color ≤5 degrees, heavy metal ions ≤0.01 mg / L; S2: First-stage reverse osmosis purification: Water from intermediate water tank 12 is sent to the first-stage reverse osmosis unit via first-stage high-pressure pump 15, and the initial purified water is stored in first-stage water tank 17; the water quality parameters are conductivity ≤10μS / cm, desalination rate ≥99%, TOC ≤0.5ppm, microbial retention rate ≥99.9%, and total ionic impurity content ≤10ppm. S3: Secondary reverse osmosis purification: Water from the primary water tank 17 is sent to the secondary reverse osmosis unit via the secondary high-pressure pump 18, and the produced pure water is stored in the secondary water tank 20; the water quality parameters are conductivity ≤1μS / cm, total desalination rate ≥99.5%, TOC ≤0.1ppm, silicon ions ≤0.05ppm, chloride ions ≤0.1ppm, suitable for pre-plating cleaning scenarios; S4: Continuous electro-desalination and purification: Water from the secondary water tank 20 is sent to the continuous electro-desalination unit 4 via the electro-desalination high-pressure pump 21, and ultrapure water is stored in the pure water tank 24; the water quality parameters are resistivity ≥18.2MΩ・cm (25℃), conductivity ≤0.055μS / cm, TOC ≤10ppb, ionic impurities ≤0.1ppb, microorganisms ≤1CFU / mL, suitable for precision rinsing scenarios; S5: Concentrate recovery: Wastewater from the primary and secondary reverse osmosis units is stored in the recovery water tank 25. After being treated by the recovery reverse osmosis module 27, the water in the recovery water tank 25 has a conductivity of ≤50μS / cm and a desalination rate of ≥98%, and is returned to the intermediate water tank 12 for recycling.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A high utilization water treatment device, characterized by: The device comprises sequentially connected raw water pretreatment unit (1), primary filtration unit (2), secondary filtration unit (3) and continuous electric desalination unit (4); the secondary filtration unit (3) is connected with pure water outlet module (6), and the continuous electric desalination unit (4) is connected with ultrapure water outlet module (7), The primary filtration unit (2) and the wastewater outlet of the secondary filtration unit (3) are connected in parallel with the recovered wastewater pretreatment unit (5), and the purified water outlet of the recovered wastewater pretreatment unit (5) is connected with the inlet of the primary filtration unit (2).

2. The high utilization water treatment device of claim 1, wherein: The raw water pretreatment unit (1) comprises sequentially connected raw water tank (9), quartz sand filter (10), activated carbon filter (11), precision filter (14) and intermediate water tank (12), and the raw water tank (9) is further connected with heating unit (8).

3. The high utilization water treatment device of claim 2, wherein: The raw water pump (13) is connected between the raw water tank (9) and the quartz sand filter (10), and the pipelines between the raw water pump (13) and the quartz sand filter (10) and between the activated carbon filter (11) and the precision filter (14) are respectively connected with dosing tank (22).

4. The high utilization water treatment device of claim 3, wherein: The primary filtration unit (2) comprises sequentially connected primary high-pressure pump (15), primary reverse osmosis module (16) and primary water tank (17). The secondary filtration unit (3) comprises sequentially connected secondary high-pressure pump (18), secondary reverse osmosis module (19) and secondary water tank (20).

5. The high utilization water treatment device of claim 4, wherein: The continuous electric desalination unit (4) comprises sequentially connected electric desalination high-pressure pump (21), continuous electric desalination module (23) and pure water tank (24).

6. The high utilization water treatment device of claim 5, wherein: The recovered wastewater pretreatment unit (5) comprises sequentially connected recovered water tank (25), high-pressure pump (26) and recovered reverse osmosis module (27).

7. The high utilization water treatment device of claim 6, wherein: The purified water outlet of the recovered reverse osmosis module (27) is connected with the intermediate water tank (12).

8. The high utilization water treatment device of claim 7, wherein: The wastewater outlet of the primary reverse osmosis module (16) is connected with the recovered water tank (25), and the wastewater outlet of the secondary reverse osmosis module (19) is connected with the recovered water tank (25).

9. The high utilization water treatment device of claim 8, wherein: The pure water outlet module (6) is connected with the secondary water tank (20), and the ultrapure water outlet module (7) is connected with the pure water tank (24).

10. A high utilization water treatment process characterized by: The method adopts the high-utilization water treatment device according to any one of claims 2-9, and comprises the following steps: S1: raw water pretreatment: tap water is subjected to three-stage filtration of quartz sand filter (10), activated carbon filter (11) and precision filter (14) and then stored in intermediate water tank (12); the water quality parameters are turbidity≤0.5 NTU, particulate matter content (≥1 μm)≤20 pieces / mL, suspended matter removal rate≥90%, residual chlorine≤0.05 mg / L, TOC≤3 ppm, colority≤5 degrees and heavy metal ion≤0.01 mg / L; S2: primary reverse osmosis purification: the water in the intermediate water tank (12) is sent to the primary reverse osmosis unit by the primary high-pressure pump (15), and the initial pure water is stored in the primary water tank (17); the water quality parameters are: conductivity ≤10 μS / cm, desalination rate ≥99%, TOC ≤0.5 ppm, microbial interception rate ≥99.9%, and total ion impurity content ≤10 ppm; S3: secondary reverse osmosis purification: the water in the primary water tank (17) is sent to the secondary reverse osmosis unit by the secondary high-pressure pump (18), and the output pure water is stored in the secondary water tank (20); the water quality parameters are: conductivity ≤1 μS / cm, total desalination rate ≥99.5%, TOC ≤0.1 ppm, silicon ion ≤0.05 ppm, chloride ion ≤0.1 ppm, and suitable for pre-plating cleaning scenarios; S4: continuous electric desalination purification: the water in the secondary water tank (20) is sent to the continuous electric desalination unit (4) by the electric desalination high-pressure pump (21), and the ultrapure water is stored in the pure water tank (24); the water quality parameters are: resistivity ≥18.2 MΩ·cm (25℃), conductivity ≤0.055 μS / cm, TOC ≤10 ppb, ion impurities ≤0.1 ppb, and microorganisms ≤1 CFU / mL, suitable for precision rinsing scenarios; S5: concentrated water recovery: the wastewater of the primary reverse osmosis unit and the secondary reverse osmosis unit is stored in the recovery water tank (25), and the water in the recovery water tank (25) is treated by the recovery reverse osmosis module (27) after treatment, the conductivity of the recovered water is ≤50 μS / cm, the desalination rate is ≥98%, and the recovered water is recycled to the intermediate water tank (12).

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